This invention relates to a power control circuit for supplying electrical power to a computer, and particularly to such a control circuit which, once activated, allows the computer itself to determine when power should be deactivated.
Such a latch circuit is sometimes subject to unpredictable signal voltage fluctuations on the deactivate signal line from the computer as the computer powers down, which fluctuations might reactivate the latch circuit and thus interfere with the proper power down operation. Therefore, the latch circuit should include means to hold it in the deactivated state once deactivation has begun. On the other hand, it is desirable to minimize current draw by the latch circuit when deactivated, particularly for motor vehicle applications. Therefore, the means preventing reactivation should have minimal current draw in its operation.